This invention relates to ring binders for holding paper and the like, and more particularly, a ring binder which is easier to open than conventional ring binders.
Conventional ring binders employ a pair of thumb or finger operated trigger mechanisms, one located at each end of a “metal”. The metal includes two or more binder rings connected to a lever movable by the trigger mechanism to open and close the binder. Heretofore, the force required to operate the trigger has been relatively substantial. One reason for this is that the metal is designed to not inadvertently open if a binder is, for example, dropped. Accordingly, conventional metals have been designed to withstand a reasonable amount of force and remain closed. While these metals have functioned well for their intended purpose, it has recently been recognized that it would be advantageous to employ a metal which, while it stays closed when dropped or otherwise mishandled, requires substantially less force by a user to open it when the user desires to open the binder.
Various approaches to easy open type ring metals are disclosed in U.S. Pat. No. 6,749,357, and published U.S. patent applications 2005/0013654, 2003/0103798, and 2003/0103797. However, the structures shown and described therein are more complex and costly than the invention described herein.